Gay marriage advocates have filed a brief with the Supreme Court inviting public signatures. The Human Rights Campaign (HRC) filed an “amicus curiae” (Friend of The Court) brief that would allow justices to hear from both the group and the public, ahead of an April hearing on whether a federal ban on same-sex marriage is unconstitutional, USA Today reported.

The first name on the list will reportedly be that of Edie Windsor, who in 2013 won a lawsuit in the Supreme Court that caused a key section of the Defense of Marriage Act to be struck down, allowing federal benefits for legally married gays and lesbians in all states. HRC officials say they haven’t heard of another case where an amicus curiae brief has been made available to the general public to sign.

"In the past when we had amicus briefs like this, it was not uncommon to have large numbers of law professors or even law students sign it," Roberta Kaplan, a lawyer with HRC, told the Knoxville News Sentinel on Monday. "But what technology here allows HRC to do here is give millions of Americans the opportunity to read the brief, and if they agree with it, to sign onto it."

Last month, Supreme Court justices agreed to hear appeals on gay marriage bans from four states -- Kentucky, Michigan, Ohio and Tennessee. All four cases were considered in a Sixth Circuit Court of Appeals ruling that upheld a state ban on gay marriage.

The Supreme Court on Monday refused to block same-sex marriages in Alabama, ahead of the ruling, which some see as an indication of how it will rule in the April case, the New York Times reported.

Justice Clarence Thomas, in his dissent on the Alabama decision, said: “This acquiescence may well be seen as a signal of the Court’s intended resolution of that question,” referring to the pending ruling.

HRC is expected to host the brief on its website from Tuesday and it will be open to signatures from the public until March 2.